www.murata-ps.com
UWR Models
Single Output, High-Density,
6 Amp/15 Watt DC/DC Converters
Typical units
PR
PRODUCT OVERVIEW
The new 1.2, 1.5V, 1.8V and 2.5V models in
Mu
Murata Power Solutions’ flagship 7-15 Watt
A-S
A-Series can source a continuous 6 Amps. This
t
is the most "low-voltage" current available from
s
a standard 1" x 2" package, and these power
con
converters exemplify Murata Power Solutions’
relentless drive to bring you more power/current,
from standard packages, without compromising
reliability or resorting to thermal specmanship.
By combining a high-frequency, high-efficiency
(to 88%), synchronous-rectifier topology with
the newest components and time-tested, fully
automated, SMT-on-pcb construction, these
UWR Models are able to bring you 7-15W (@
up to 6A) in the standard 1" x 2" package from
which most competitors can only get 5-10W (@
3-4A). All UWR’s deliver their full output power
over ambient temperature ranges from –40°C
to as high as +70°C (model and input voltage
dependent) without heat sinks or supplemental
forced-air cooling. Devices derate to +100°C.
Output voltages are 1.2, 1.5, 1.8, 2.5, 3.3, 5,
12 or 15 Volts. Input voltage ranges are 10-18V
(D12 models), 18-36V (D24 models) or 36-75V
(D48 models). All models feature input pi filters,
input undervoltage and overvoltage lockout, input
reverse-polarity protection, output overvoltage
protection, output current limiting, and continuous
short-circuit protection. On/off control and output-
trim functions are optional (see Optional Functions).
All models are designed to meet IEC950, UL1950
and EN60950-1, 2nd Edition safety requirements.
D48 models (36-75V inputs) are CE marked.
UWR 7-15W DC/DC’s are packaged in low-
cost, light-weight, diallyl phthalate (UL94V-0
rated) plastic packages with standoffs. EMC
compliance is achieved via a low-noise design
rather than through expensive metal shielding.
FEATURES
1.2-2.5V
OUT
models source 6 Amps
3.3V
OUT
models source 4.25 Amps
5/12/15V
OUT
models deliver full 15 Watts
Synchronous-rectifier topologies
Guaranteed efficiencies to 88%
Choice of 3 input voltage ranges:
10-18V, 18-36V, 36-75V
–40 to +60/70qC ambient w/o derating
Fully isolated (1500Vdc); I/O protected
Meets UL/IE/EN60950-1 certification,
2nd Edition
CE mark (75V
IN
models)
Standard 1" x 2" packages and pinouts
Optional V
OUT
trim and on/off control
+V
IN
(1)
+V
OUT
(4)
SWITCH
CONTROL
COMMON
(6)
–V
IN
(2)
PWM
CONTROLLER
OPTO
ISOLATION
REFERENCE &
ERROR AMP
TRIM
(5)
(OPTIONAL)
ON/OFF
CONTROL
(3)
(OPTIONAL)
UVLO & OVLO
COMPARATORS
Typical topology is shown.
Figure 1. Simplified Schematic
For full details go to
www.murata-ps.com/rohs
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22 Jun 2010
email: sales@murata-ps.com
MDC_UWR_7-15.F09
Page 1 of 12
UWR Models
Single Output, High-Density,
6 Amp/15 Watt DC/DC Converters
Performance Specifications and Ordering Guide
➀
ORDERING GUIDE
Output
Root Model
➆
UWR-1.2/6000-D12A-C
UWR-1.2/6000-D24A-C
UWR-1.2/6000-D48A-C
UWR-1.5/6000-D12A-C
UWR-1.5/6000-D24A-C
UWR-1.5/6000-D48A-C
UWR-1.8/6000-D12A-C
UWR-1.8/6000-D24A-C
UWR-1.8/6000-D48A-C
UWR-2.5/6000-D12A-C
UWR-2.5/6000-D24A-C
UWR-2.5/6000-D48A-C
UWR-3.3/4250-D12A-C
UWR-3.3/4250-D24A-C
UWR-3.3/4250-D48A-C
UWR-3.3/4500-D48ANT-C
➄
UWR-5/3000-D12A-C
UWR-5/3000-D24A-C
UWR-5/3000-D48A-C
UWR-5/3000-D48ANST-C
➅
UWR-12/1250-D12A-C
UWR-12/1250-D24A-C
UWR-12/1250-D48A-C
UWR-15/1000-D12A-C
UWR-15/1000-D24A-C
UWR-15/1000-D48A-C
Vout
(Volts)
1.2
1.2
1.2
1.5
1.5
1.5
1.8
1.8
1.8
2.5
2.5
2.5
3.3
3.3
3.3
3.3
5
5
5
5
12
12
12
15
15
15
Iout (mA)
6000
6000
6000
6000
6000
6000
6000
6000
6000
6000
6000
6000
4250
4250
4250
4500
3000
3000
3000
3000
1250
1250
1250
1000
1000
1000
R/N (mV p-p)
➁
Typ.
40
40
40
30
30
30
30
30
30
30
30
30
85
45
85
85
85
85
85
85
85
85
85
85
85
85
Max.
75
75
75
55
55
55
55
55
55
55
50
55
100
70
100
100
100
100
100
100
100
100
100
100
100
100
Regulation (max.)
Line
Load
➂
±0.2%
±0.5%
±0.05% ±0.5%
±0.2%
±0.5%
±0.1%
±0.5%
±0.1%
±0.5%
±0.1%
±0.5%
±0.1%
±0.5%
±0.1%
±0.5%
±0.1%
±0.5%
±0.1%
±0.5%
±0.075% ±0.25%
±0.1%
±0.5%
±0.2%
±0.5%
±0.05% ±0.15%
±0.2%
±0.5%
±0.2%
±0.5%
±0.2%
±0.3%
±0.2%
±0.3%
±0.2%
±0.3%
±0.2%
±0.3%
±0.2%
±0.2%
±0.2%
±0.2%
±0.2%
±0.2%
➃
➄
➅
➆
Input
Vin nom.
(Volts)
12
24
48
12
24
48
12
24
48
12
24
48
12
24
48
48
12
24
48
48
12
24
48
12
24
48
Range
(Volts)
10-18
18-36
36-75
10-18
18-36
36-75
10-18
18-36
36-75
10-18
18-36
36-75
10-18
18-36
36-75
36-75
10-18
18-36
36-75
36-75
10-18
18-36
36-75
10-18
18-36
36-75
Iin
(mA)
➃
Efficiency
Min.
Typ.
78%
80%
80%
79.5%
80%
80.5%
83%
84.5%
85%
86%
86%
86%
86%
87%
87%
87%
85%
88%
88%
88%
85%
87%
87%
85%
87%
87%
Package
(Case, Pinout)
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
C14, P22
80/769
76%
45/375
78%
80/188
78%
75/914
77.5%
40/454
78%
25/226
78.5%
70/1084
81%
35/539
82.5%
25/268
83%
80/1489
83%
45/727 84.75%
25/367
84%
80/1375
83%
45/672
85%
35/336
85%
35/356
85%
110/1471 83%
55/710
85.5%
35/355
85.5%
35/355
85.5%
45/1471
45/718
20/359
45/1471
45/718
20/359
82.5%
85%
85%
82.5%
85%
85%
±0.3%
±0.3%
±0.3%
±0.3%
±0.3%
±0.3%
➀
Typical at T
A
= +25°C under nominal line voltage and full-load conditions, unless otherwise noted.
➁
Ripple/Noise (R/N) is tested/speciifed over a 20MHz bandwidth. All models are specified with
two external 0.47μF multi-layer ceramic capacitors located 2-3 inches from the module being
tested.
➂
Load regulation is specified over 10%-100% load conditions. 1.5-5V models are stable and
regulate under no-load conditions. 12/15V models have minimum loading requirements See
Performance/Functional Specifications.
Nominal line voltage, no-load/full-load conditions.
See
page 12.
Special trim version. See Trim Equations, page 5. Quantity order required.
Please refer to the
Part Number Structure
for additional options when ordering.
MECHANICAL SPECIFICATIONS
50.8
2.00
25.4
1.00
For Part Number Structure, please see
page 12.
SIDE VIEW
Pin
1
2
3
I/O Connections
Function P22
Pin
Function P22
+Input
4
+Output
–Input
5
Trim*
On/Off Control*
6
Common
5.1 MIN
.20 MIN
END VIEW
12.07
.475
*Pins 3 and 5 are optional.
See Optional Functions and
Technical Notes for details.
6X
1.02±0.05
.040±.002
PLASTIC CASE
.020 STANDOFF
(4 PLACES)
Dimensions are in inches (mm) shown for ref. only.
Third Angle Projection
Standard pin length is shown.
Please refer to the Part Number
Structure for special order pin
lengths.
BOTTOM VIEW
20.32
.800
15.2
.60
4
1
2
3
5
6
10.16
.400
20.32
.800
Tolerances (unless otherwise specified):
.XX ± 0.02 (0.5)
.XXX ± 0.010 (0.25)
Angles ± 2˚
Components are shown for reference only.
12.70
.500
7.62
.300
2.5
.10
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MDC_UWR_7-15.F09
Page 2 of 12
UWR Models
Single Output, High-Density,
6 Amp/15 Watt DC/DC Converters
Performance/Functional Specifications
Input
Typical @ T
A
= +25°C under nominal line voltage and full-load conditions, unless noted.
➀➁
Dynamic Characteristics (continued)
Input Voltage Range:
D12A Models
D24A Models
D48A Models
Overvoltage Shutdown:
D12A Models
D24A Models
D48A Models
Start-Up Threshold:
➂
D12A Models
D24A Models
D48A Models
Undervoltage Shutdown:
➂
D12A Models
D24A Models
D48A Models
Input Current:
Normal Operating Conditions
Standby Mode (Off, OV, UV)
Input Filter Type
Reverse-Polarity Protection
On/Off Control
(Optional, Pin 3):
➃ ➄
D12AC, D24AC, & D48AC Models
D12AN, D24AN, & D48AN Models
10-18 Volts (12V nominal)
18-36 Volts (24V nominal)
36-75 Volts (48V nominal)
18.5-21 Volts (20V typical)
37-41 Volts (38V typical)
77-81 Volts (78.5V typical)
9.4-10 Volts (9.6V typical)
16.5-18 Volts (17V typical)
34-36 Volts (35V typical)
7-8.5 Volts (8V typical)
15.5-17.5 Volts (16.5V typical)
32.5-35.5 Volts (34V typical)
See Ordering Guide
5mA
Pi
Brief duration, 10A maximum
On = open or 13V to +V
IN
, I
IN
= 1-5mA typ.
Off = 0-0.8V, I
IN
= 3-12mA typ.
On = 0-0.8V, I
IN
= 3-12mA typ.
Off = open or 3.3-5.5V, I
IN
= 1-5mA typ.
Switching Frequency
1.2V models
1.5V D48 models
1.8V D12 models
1.8V D24 models
1.8V D48 models
2.5 and 1.5 D12/D24 models
3.3-12V models
250-300kHz ±30kHz, model dependent
260kHz (±30kHz)
280kHz (±30kHz)
250kHz (±30kHz)
210kHz (±20kHz)
340kHz (±40kHz)
310-345kHz ±10%, model dependent
Environmental
Operating Temperature
(Ambient):
(See Derating Curves)
Case Temperature:
Maximum Allowable
Storage Temperature
–40 to +85°C with Derating
+100°C
–40 to +105°C
Physical
Dimensions
Shielding
Case Material
Pin Material
Weight
2" x 1" x 0.475" (51 x 25 x 12.1mm)
None
Diallyl phthalate, UL94V-0 rated
Gold-plated copper alloy with nickel underplate
1.4 ounces (39.7 grams)
Output
V
OUT
Accuracy
(50% load):
±1.5% (±2% for model UWR-1.2/6000)
Minimum Loading for Specification:
➁
1.2V/1.5V/1.8V/2.5V/3.3V/5V Outputs No load
12V/15V Outputs
10% of I
OUT
max.
Minimum Loading for Stability:
➁
1.2V/1.5V/1.8V/2.5V/3.3V/5V Outputs
12V/15V Outputs
Ripple/Noise
(20MHz BW)
➀ ➅
Line/Load Regulation
Efficiency
Isolation Voltage:
Input-to-Output
Isolation Capacitance
Isolation Resistance
Current Limiting:
1.2V-5V Outputs
12V and 15V Outputs
Overvoltage Protection
Temperature Coefficient
No load
25mA
See Ordering Guide
See Ordering Guide
See Ordering Guide
1500Vdc minimum (functional)
470pF
100M:
Hiccup technique, auto-recovery
Power-limiting technique, auto-recovery
Zener/transorb clamp, magnetic feedback
±0.04% per °C
Dynamic Characteristics
➀
All models are specified with two external 0.47μF multi-layer ceramic capacitors installed across
their output pins.
➁
See Minimum Output Loading Requirements under Technical Notes.
➂
See Technical Notes for details.
➃
The On/Off Control and Trim functions are optional and must be installed by MPS. See Optional
Functions or contact MPS for details.
➄
The On/Off Control is designed to be driven with open-collector logic or the application of appro-
priate voltages (referenced to –Input, pin 2). Applying a voltage to the On/Off Control pin when
no input voltage is applied to the converter may cause permanent damage. See Technical Notes.
➅
Output noise maybe further reduced with the addition of additional external output capacitors.
See Technical Notes.
➆
Operating temperature range without derating is model and input-voltage dependent. See
Temperature Derating.
➇
RoHS-6 hazardous substance compliance does not claim EU RoHS exemption 7b (lead in solder).
Absolute Maximum Ratings
Input Voltage:
Continuous:
D12 Models
D24 Models
D48 Models
Transient (100msec):
D12 Models
D24 Models
D48 Models
Input Reverse-Polarity Protection
Output Overvoltage Protection:
1.2V/1.5/1.8V Outputs
2.5V/3.3V Outputs
5V/12V/15V Outputs
Output Current
22 Volts
44 Volts
88 Volts
50 Volts
50 Volts
100 Volts
Current must be <10 Amps. Brief duration
only. Fusing recommended.
2.1/2.2/2.3 Volts, unlimited duration
TBD/3.4/4.4 Volts, unlimited duration
7.1/16/18 Volts, unlimited duration
Current limited. Devices can withstand sus-
tained output short circuits without damage.
+100°C
–40 to +105°C
Transient Response
(50% load step)
1.2V-2.5V models
3.3V-15V models
Start-Up Time:
➂
V
IN
to V
OUT
On/Off to V
OUT
200μsec max. to ±2% of final value
200μsec max. to ±1.5% of final value
50msec
30msec
Case Temperature
Storage Temperature
Lead Temperature
See soldering guidelines
These are stress ratings. Exposure of devices to greater than any of these conditions may
adversely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Specifications Table is not implied.
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MDC_UWR_7-15.F09
Page 3 of 12
UWR Models
Single Output, High-Density,
6 Amp/15 Watt DC/DC Converters
Floating Outputs
Since these are isolated DC/DC converters, their outputs are "floating."
Designers will usually use the output Common (pin 6) as the ground/return of
the load circuit. You can, however, use the +Output (pin 4) as ground/return to
effectively reverse the output polarity.
Minimum Output Loading Requirements
1.2 to 5V models employ a synchronous-rectifier design topology. All models
regulate within spec and are stable under no-load conditions. 12/15V models
employ a traditional forward architecture and require 10% loading (125mA for
12V models, 100mA for 15V models) to achieve their listed regulation specs.
12/15V models also have a minimum-load-for-stability requirement (20mA).
For 12/15V models, operation below 20mA or 10% loading will be stable but
regulation may degrade. A 100μF output capacitor is recommended below 10%
loading. Users should verify whether this relaxed regulation will have any effect
on output circuits. If so, add a small load of 10% or greater.
Operation under no-load conditions will not damage 12/15V converters.
However they may not meet all listed specifications.
Filtering and Noise Reduction
All A-Series UWR DC/DC Converters achieve their rated ripple and noise
specifications using the external input and output capacitors specified in the
Performance/Functional Specifications table. In critical applications, input/
output noise may be further reduced by installing additional external I/O caps.
Input capacitors should be selected for bulk capacitance, low ESR and high
rms-ripple-current ratings. Output capacitors should be selected for low ESR and
appropriate frequency response. All caps should have appropriate voltage ratings
and be mounted 2-3 inches from the converter to achieve published ratings. The
most effective combination of external I/O capacitors will be a function of your
particular load and layout conditions.
Input Fusing
Certain applications and/or safety agencies may require the installation of
fuses at the inputs of power conversion components. Fuses should also be
used if the possibility of sustained, non-current-limited, input-voltage polarity
reversals exists. For MPS's A-Series UWR 7-15 Watt DC/DC Converters, you
should use fast-blow type fuses with values no greater than the following.
V
IN
Range
"D12A" Models
"D24A" Models
"D48A" Models
Fuse Value
3 Amps
2 Amps
1 Amp
red camera is a another alternative which avoids the TC heatsinking effect.
But the IR camera must be calibrated frequently and accurately. Remember
too that it is quite difficult to accurately measure airflow right at the converter.
Murata Power Solutions uses a calibrated wind tunnel with large amounts
of data history. Because of thermal time constants, allow plenty of time for
temperature stabilization.
Trimming Output Voltages
These converters have a trim capability (pin 5) that allows users to adjust the
output voltage ±5%. Adjustments to the output voltage can be accomplished
via a trim pot, Figure 2, or a single fixed resistor as shown in Figures 3 and 4.
A single fixed resistor can increase or decrease the output voltage depend-
ing on its connection. Fixed resistors should have an absolute TCR less than
100ppm/°C to minimize sensitivity to changes in temperature.
A single resistor connected from the Trim (pin 5) to the +Output (pin 4), see
Figure 3, will decrease the output voltage. A resistor connected from the Trim
(pin 5) to Output Common (pin 6) will increase the output voltage.
Trim adjustment greater than 5% can have an adverse effect on the con-
verter's performance and is not recommended.
1
+INPUT
4
+OUTPUT
2
–INPUT
TRIM
5
20kΩ
5-22
Turns
LOAD
3
ON/OFF
CONTROL
COMMON
6
Figure 2. Trim Connections Using A Trim Pot
1
+INPUT
+OUTPUT
4
R
TRIM DOWN
2
–INPUT
TRIM
5
LOAD
3
ON/OFF
CONTROL
COMMON
6
Figure 3. Trim Connections To Decrease Output Voltage Using Fixed Resistors
Maximum Case Temperature
The +100 degree C. maximum outside case temperature specification is based
on much empirical testing on encapsulated units. Those tests show that if
the case exterior can be maintained at or below +100C., the hottest internal
components’ package temperatures will not exceed +128C. because of the
internal temperature gradient to the exterior case. This latter +128C. internal
figure is a safety margin offering more protection for the internal components.
The +100C. case specification must be achieved by the user’s combination of
lower output current and/or higher airflow.
If you attempt any of your own case temperature testing, please be aware of
the heatsinking effect of attaching wired thermocouples to surfaces. An infra-
1
+INPUT
+OUTPUT
4
2
–INPUT
TRIM
5
LOAD
R
TRIM UP
3
ON/OFF
CONTROL
COMMON
6
Figure 4. Trim Connections To Increase Output Voltage Using Fixed Resistors
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22 Jun 2010
MDC_UWR_7-15.F09
Page 4 of 12
UWR Models
Single Output, High-Density,
6 Amp/15 Watt DC/DC Converters
Model
Trim Equation
R
T
DOWN
(k ) =
R
T
UP
(k ) =
R
T
DOWN
(k ) =
R
T
UP
(k ) =
R
T
DOWN
(k ) =
R
T
UP
(k ) =
R
T
DOWN
(k ) =
R
T
UP
(k ) =
5.32(V
O
–
0.7)
1.2
–
V
O
3.73
V
O
–
1.2
–2
–2
Model
Trim Equation
R
T
DOWN
(k ) =
1.27
–8.25
K
3.3
–
V
O
where
K =
3.3
UWR-1.2/6000-D12A
UWR-1.2/6000-D24A
UWR-1.2/6000-D48A
UWR-1.5/6000-D12A
UWR-1.5/6000-D24A
UWR-1.5/6000-D48A
UWR-3.3/4500-D48ANT
–2
1.6(V
O
–
1.23)
1.5
–
V
O
1.968
V
O
–
1.5
–2
R
T
UP
(k ) =
0.78
–6.2
K
V
O
–
3.3
where
K =
3.3
2.49(V
O
–
2.527)
–15
5
–
V
O
6.292
V
O
–
5
–15
UWR-1.8/6000-D12A
UWR-1.8/6000-D24A
UWR-1.8/6000-D48A
UWR-2.5/6000-D12A
UWR-2.5/6000-D24A
UWR-2.5/6000-D48A
UWR-3.3/4250-D12A
UWR-3.3/4250-D24A
UWR-3.3/4250-D48A
0.995(V
O
–
1.24)
–2.49
1.8
–
V
O
1.23
V
O
–
1.8
–2.49
–11
UWR-5/3000-D12A
UWR-5/3000-D24A
UWR-5/3000-D48A
R
T
DOWN
(k ) =
R
T
UP
(k ) =
R
T
DOWN
(k ) =
2(V
O
–
1.24)
2.5
–
V
O
2.48
V
O
–
2.5
–11
7.5(V
O
–
1.24)
5.0
–
V
O
9.3
–10
V
O
–
4.997
6.34(V
O
–
5.714)
–49.9
12
–
V
O
36.23
V
O
–
12
–49.9
UWR-5/3000-D48ANST
R
T
UP
(k ) =
2.49(V
O
–
1.27)
R
T
DOWN
(k ) =
3.3
–
V
O
R
T
UP
(k ) =
3.16
V
O
–
3.3
–16.9
–16.9
UWR-12/1250-D12A
UWR-12/1250-D24A
UWR-12/1250-D48A
R
T
DOWN
(k ) =
R
T
UP
(k ) =
R
T
DOWN
(k ) =
R
T
UP
(k ) =
UWR-15/1000-D12A
UWR-15/1000-D24A
UWR-15/1000-D48A
Soldering Guidelines
Murata Power Solutions recommends the specifications below when install-
ing these converters. These specifications vary depending on the solder type.
Exceeding these specifications may cause damage to the product. Be cautious
when there is high atmospheric humidity. Your production environment may
differ; therefore please thoroughly review these guidelines with your process
engineers.
Wave Solder Operations for through-hole mounted products (THMT)
7.87(V
O
–
7.136)
–63.4
15
–
V
O
56.16
V
O
–
15
–63.4
Start-Up Threshold and Undervoltage Shutdown
Under normal start-up conditions, devices will not begin to regulate until the
ramping-up input voltage exceeds the Start-Up Threshold Voltage (35V for
"D48A" models). Once operating, devices will not turn off until the input volt-
age drops below the Undervoltage Shutdown/Lockout limit (34V for "D48A"
models). Subsequent re-start will not occur until the input is brought back up to
the Start-Up Threshold. This built-in hysteresis obviously avoids any indetermi-
nate on/off situations at a single voltage.
Start-Up Time
The V
IN
to V
OUT
Start-Up Time is the interval between the time at which a ramp-
ing input voltage crosses the turn-on threshold point and the fully-loaded output
voltage enters and remains within its specified accuracy band. Actual measured
times will vary with input source impedance, external input capacitance, and the
slew rate and final value of the input voltage as it appears to the converter.
The On/Off to V
OUT
Start-Up Time assumes the converter is turned off via the
On/Off Control with the nominal input voltage already applied to the converter.
The specification defines the interval between the time at which the converter
is turned on and the fully-loaded output voltage enters and remains within its
specified accuracy band.
Accuracy of adjustment is subject to tolerances or resistor values and
factory-adjusted output accuracy. V
O
= desired output voltage.
For Sn/Ag/Cu based solders:
Maximum Preheat Temperature
Maximum Pot Temperature
Maximum Solder Dwell Time
For Sn/Pb based solders:
Maximum Preheat Temperature
Maximum Pot Temperature
Maximum Solder Dwell Time
105° C.
250° C.
6 seconds
115° C.
270° C.
7 seconds
www.murata-ps.com
22 Jun 2010
email: sales@murata-ps.com
MDC_UWR_7-15.F09
Page 5 of 12
Microchip MCU
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